1. Field of the Invention
The present invention relates to a developer carrying member and a developing apparatus used for an image forming apparatus.
2. Description of the Related Art
The triboelectric charge amount of the toner is susceptible to the surface condition of the developer carrying member. In Japanese Patent Application Laid-Open No. H08-030088, the triboelectric charge amount distribution is controlled by providing a charge controlling agent-containing resin layer on the surface of the developer carrying member. Japanese Patent Application Laid-Open No. 2001-312136 has proposed a developer carrying member including in the resin layer thereof as a charge controlling agent a quaternary ammonium base-containing copolymer. According to this constitution, by the ionization of the negatively charged counterion of the quaternary ammonium base, the charge controlling agent is made to be ion conductive, and accordingly the volume resistance of the resin layer is decreased to some extent. Accordingly, the image failure such as ghost or fog is improved. Japanese Patent Application Laid-Open No. 2007-025593 has proposed a developer carrying member including in the resin layer thereof a positively chargeable resin and a specific carbon black. According to such a constitution, by using a carbon black being small in particle size and having lubricity, a uniform and high triboelectric charge can be imparted to the toner. The contamination of the surface of the developer carrying member due to the fusion bonding of the toner or the toner attachment can also be suppressed.